袁晓红

that与what的区别

1. that只起连接作用，不充当句子的任何成分，可以引导主语从句、宾语从句和表语从句。

①主语从句：常用it做形式主语，that引导真正的主语或者直接用that引导主语从句。

It made his parents disappointed that he was addicted to playing computer games.

他沉迷于电脑游戏使父母很失望。

That she was late for class again made the teacher very angry.

她上课又迟到使老师很生气。

②宾语从句：当一个句子引导两个或多个并列的宾语从句时，只有第一个that可省略；it作形式宾语，that引导真正的宾语时不能省略；that从句一般不充当介词的宾语，偶尔可以作except的宾语。

She said （that） she was going to Shanghai and that she could returned after several months.

她说她准备去上海并且要过几个月之后才回来。

I have made it clear that I disagreed to the decision.

我已清楚表明我不同意这个决定。

The article is well written except that there are some spelling mistakes.

除了一些拼写错误之外，这篇文章写得很好。

③表语从句

The good news is that they won the football game.

好消息是他们赢了这场足球赛。

2. what在名词性从句中可充当主语、宾语和表语，意义上相当于the thing（s） that， 同样可以引导主语从句、宾语从句和表语从句。

①主语从句：引导主语从句时，其谓语动词的单复数由表语的单复数来决定。

What we badly need are those equipments.

我们急需的是那些设备。

What delighted us most was that he performed extremly well in the competition.

让我们最高兴的是他在竞赛中表现得好极了。

②宾语从句：可以在句中作介词宾语

I have no idea of what he has said at the meeting.

我不知道他在会议上说过什么。

A. modern city was set up on what used to be a wasteland.

一个现代化的城市建在曾经是一块废地的地方。

③表语从句

This is what I want to tell you about.

这就是我想要告诉你的。

Whether与if 的区别

1. 作“是否”讲，在ask， know， tell， doubt， wonder， see， ask， find out等词后引导宾语从句时，if和whether可以互换。

I dont know whether/if he will attend the wedding.

我不知道他是否会参加婚礼。

We doubt whether/if the news is true.

我们怀疑这消息是否是真的。

2. 在下列情况下常用whether而不用 if：

①引导主语从句、表语从句和同位语从句。

Whether he comes makes no difference. （主语从句）

他来不来都不重要。

The question is whether the experiment is worth doing. （表语从句）

问题是这个实验是否值得做。

We have some doubt whether he can finish the task on time. （同位语从句）